﻿// Copyright (c) 2014 AlphaSierraPapa for the SharpDevelop Team
// 
// Permission is hereby granted, free of charge, to any person obtaining a copy of this
// software and associated documentation files (the "Software"), to deal in the Software
// without restriction, including without limitation the rights to use, copy, modify, merge,
// publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons
// to whom the Software is furnished to do so, subject to the following conditions:
// 
// The above copyright notice and this permission notice shall be included in all copies or
// substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
// INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
// PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE
// FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
// DEALINGS IN THE SOFTWARE.

using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Text;
using System.Windows.Controls;
using System.Windows;
using System.Windows.Controls.Primitives;
using System.Windows.Media;
using System.Windows.Input;
using System.ComponentModel;
using System.Collections.Specialized;
using Goat.Controls.TreeView;

namespace Goat.Controls.TreeView.Controls
{
    public class SharpTreeNodeView : Control
    {
        static SharpTreeNodeView()
        {
            DefaultStyleKeyProperty.OverrideMetadata(typeof(SharpTreeNodeView),
                                                     new FrameworkPropertyMetadata(typeof(SharpTreeNodeView)));
        }

        public static readonly DependencyProperty TextBackgroundProperty =
            DependencyProperty.Register("TextBackground", typeof(Brush), typeof(SharpTreeNodeView));

        public Brush TextBackground
        {
            get { return (Brush)GetValue(TextBackgroundProperty); }
            set { SetValue(TextBackgroundProperty, value); }
        }

        public SharpTreeNode Node
        {
            get { return DataContext as SharpTreeNode; }
        }

        public SharpTreeViewItem ParentItem { get; private set; }

        public static readonly DependencyProperty CellEditorProperty =
            DependencyProperty.Register("CellEditor", typeof(Control), typeof(SharpTreeNodeView),
                                        new FrameworkPropertyMetadata());

        public Control CellEditor
        {
            get { return (Control)GetValue(CellEditorProperty); }
            set { SetValue(CellEditorProperty, value); }
        }

        public SharpTreeView ParentTreeView
        {
            get { return ParentItem.ParentTreeView; }
        }

        internal LinesRenderer LinesRenderer { get; private set; }

        public override void OnApplyTemplate()
        {
            base.OnApplyTemplate();
            LinesRenderer = Template.FindName("linesRenderer", this) as LinesRenderer;
            UpdateTemplate();
        }

        protected override void OnVisualParentChanged(DependencyObject oldParent)
        {
            base.OnVisualParentChanged(oldParent);
            ParentItem = this.FindAncestor<SharpTreeViewItem>();
            ParentItem.NodeView = this;
        }

        protected override void OnPropertyChanged(DependencyPropertyChangedEventArgs e)
        {
            base.OnPropertyChanged(e);
            if (e.Property == DataContextProperty)
            {
                UpdateDataContext(e.OldValue as SharpTreeNode, e.NewValue as SharpTreeNode);
            }
        }

        void UpdateDataContext(SharpTreeNode oldNode, SharpTreeNode newNode)
        {
            if (newNode != null)
            {
                newNode.PropertyChanged += Node_PropertyChanged;
                if (Template != null)
                {
                    UpdateTemplate();
                }
            }
            if (oldNode != null)
            {
                oldNode.PropertyChanged -= Node_PropertyChanged;
            }
        }

        void Node_PropertyChanged(object sender, PropertyChangedEventArgs e)
        {
            if (e.PropertyName == "IsEditing")
            {
                OnIsEditingChanged();
            }
            else if (e.PropertyName == "IsLast")
            {
                if (ParentTreeView.ShowLines)
                {
                    foreach (var child in Node.VisibleDescendantsAndSelf())
                    {
                        var container = ParentTreeView.ItemContainerGenerator.ContainerFromItem(child) as SharpTreeViewItem;
                        if (container != null)
                        {
                            container.NodeView.LinesRenderer.InvalidateVisual();
                        }
                    }
                }
            }
            else if (e.PropertyName == "IsExpanded")
            {
                if (Node.IsExpanded)
                    ParentTreeView.HandleExpanding(Node);
            }
        }

        void OnIsEditingChanged()
        {
            var textEditorContainer = Template.FindName("textEditorContainer", this) as Border;
            if (Node.IsEditing)
            {
                if (CellEditor == null)
                    textEditorContainer.Child = new EditTextBox() { Item = ParentItem };
                else
                    textEditorContainer.Child = CellEditor;
            }
            else
            {
                textEditorContainer.Child = null;
            }
        }

        void UpdateTemplate()
        {
            var spacer = Template.FindName("spacer", this) as FrameworkElement;
            spacer.Width = CalculateIndent();

            var expander = Template.FindName("expander", this) as ToggleButton;
            if (ParentTreeView.Root == Node && !ParentTreeView.ShowRootExpander)
            {
                expander.Visibility = Visibility.Collapsed;
            }
            else
            {
                expander.ClearValue(VisibilityProperty);
            }
        }

        internal double CalculateIndent()
        {
            var result = 19 * Node.Level;
            if (ParentTreeView.ShowRoot)
            {
                if (!ParentTreeView.ShowRootExpander)
                {
                    if (ParentTreeView.Root != Node)
                    {
                        result -= 15;
                    }
                }
            }
            else
            {
                result -= 19;
            }
            if (result < 0)
            {
                Debug.WriteLine("Negative indent level detected for node " + Node);
                result = 0;
            }
            return result;
        }
    }
}
